Silver halide emulsions containing magenta - colored cyan - forming couplers



Sept. 30, 1969 OPTICAL DENSITY OPTICAL DENSITY MAKQTO YOSHIDA ET AL SILVER HALIDE EMULSIONS CONTAINING MAGENTA-COLORED CYAN-FORMING COUPLERS Filed Jan. 24, 1966 FIGI WAVE LENGTH Imp) OPTICAL DENSITY L06 EXPOSURE sbo s60 WAVE LENGTH Im 1) FIGS INVENTORS MAKOTO YOSHIDA I KEISUKE SHIBA AKIO OKUMURA ATTORNEYS United States Patent 3,469,986 SILVER HALIDE EMULSIONS CONTAINING MAGENTA COLORED CYAN FORMING COUPLERS Makoto Yoshida, Keisuke Shiba, and Akio Okumura, Mi-

nami-Ashigara maehi, Japan, assignors to Fuji Shashin Film Kabushiki Kaisha, Kanagawa, Japan Filed Jan. 24, 1966, Ser. No. 522,556 Claims priority, application Japan, Jan. 23, 1965, ill/3,281 Int. Cl. G03c 1/40 US. Cl. 96-400 ABSTRACT OF THE DISCLOSURE 9 Claims A color photographic silver halide emulsion containing a magenta color cyan coupler having remarkable auto-masking action represented by the formula 0 ONE SOsM (E O3M)n wherein R represents an alkyl group having more than 10 carbon atoms; M represents a member selected from the group consisting of hydrogen, an alkali metal, an

This invention relates to color photography and particularly to colored cyan couplers for use in photographic processes.

Almost all of the cyan couplers used in the color image formation of color photography are l-naphthol-Z-carboxylic acid derivatives or aminophenol derivatives. In using these couplers by their being added to a photographic emulsion, a long chain alkyl radical is introduced into the molecule to prevent the difiusion of the added coupler from the layer in which it is added to another layer. Also, more than one carboxylic or sulfonic acid group, as alkali solubilizing groups, are introduced to disperse the coupler homogeneously in a photographic emulsion layer. Also, the coupler is often provided with oleophilic proper-ties in order to dissolve it in an organic solvent, called a coupler solvent hereinafter. The cyan image obtained by coupling of these couplers with an oxidized color developer have undesirable absorption in the blue and more especially green region.

In US. Patents 2,449,966 and 2,455,169 there are described cyan couplers in which the 4-position of the l-naphthol-Z-carboxylic acid derivative is substituted by an arylazo group. These are useful to correct the undesirable absorption of the cyan dyes. Colored cyan couplers which have considerable blue absorption are easily provided, but it is rather difiicult to provide colored cyan couplers which have sufficient green absorption to obtain eifective masking. To obtain effective masking, a coupler which has as much green absorption as possible, that ice is, a magenta-colored cyan coupler, is required. It is also necessary that there be little color change of the colored coupler based upon change in the pH value of the color processing solution. It is further important that the use of a coupler solvent for the addition of coupler to an emulsion is very disadvantageous, because the thickness of emulsion layer is required to be as small as possible for the improvement of sharpness of image in a color sensitive material. While it is very advantageous, therefore, to add a coupler dissolved in alkali to an emulsion layer, the colored coupler, in general, isapt to providea considerable desensitization and to fog the emulsion. As a result, this makes it diflicult to manufacture a high sensitivity color photographic material containing a colored coupler which corrects the undesirable absorption of cyan dye.

We have described in Japanese application No. 62,440/ 63, which corresponds to US. Patent 3,386,830, that colored cyan couplers represented by the general formula:

OH OR wherein R represents alkyl radical containing more than 10 carbon atoms; M represents hydrogen, an alkali metal, an ammonium group and -H.HN (R") wherein p+q=3, p and q are integers of from 0 to 3 and R" is a lower alkyl radical; Y is a member selected from the group consisting of -COOM, 40 M and a carboalkoxy group; and n is 1 or 2, show good masking effect. We have found colored cyan couplers having excellent properties from our further research.

It is, therefore, an object of the present invention to provide alkali-soluble, magenta-colored, cyan couplers which show little color change depending on the pH value of the color processing solution. A further object is to provide magenta-colored, cyan couplerswhich show no. desensitization and little occurrence of fog. Other objects will appear from the following description and claims.

wherein R represents an alkyl group having more than 10 carbon atoms; M represents hydrogen, an alkali metal,

an ammonium group, or H.NH,,(R") wherein p+q=3, p and q are integers of from to 3 and R" 'represents'alower alkyl group; and n is 1 01*2.

As shown in the general formula mentioned above, the coupler of this invention has good solubility in aqueous alkali solutions because the anilide nucleus at the -2-position of naphthol nucleus contains a sulfo group as shifts the maximum wave length of spectral absorption 'in a film to a longer wave length, whereby the spectrum absorption in the film is improved to a great extent. In the coupler of this invention, an alkoxy group containing more than carbon atoms together with a sulfo group is introduced into the 0-position of the amido group in the anilide nucleus at the 2-position of the naphthol nucleus. It is a feature of the chemical structure of the coupler of this invention that it is-provided with the property of being diffusion-fast by virtue of a long chain alkoxy group without loss of its excellent color property.

The coupler of this invention is characterized by containing a lit-naphthylazo group substituted by a sulfo group at 4-position of naphthol nucleus. As shown in FIG. 1, the colored coupler which contains the naphthylazo group demonstrates larger bathochromic shifts than the coupler containing a substituted or unsubstituted phenylazo group. A colored coupler containing unsubstituted naphthylazo group, however, has undesirably high blue absorption and also red absorption. This undesirable tendency is less in the fi-naphthylazo group than in tat-naphthylazo group. In FIG. 1, A contains a phenylazo group, B tat-naphthylazo, and C B-naphthylazo group.

The introduction of the sulfo group into ,B-naphthylazo group not only improves greatly the solubility in aqueous alkali solution but, more significantly, reduces the undesirable blue and red absorption to a great extent and remarkably improves the spectral absorption in the film. That is, the maximum absorption wave length in the film is about 20 m longer compared with the maximum absorption wave length in aqueous solution, and the blue absorption is reduced to provide a very desirable magenta, without red absorption (see FIG. 2). Additionally, the change of color caused by the pH-value of the processing solution is reduced. From the facts mentioned above, it will be understood how important and necessary to the invention is the introduction of the fit-naphthylazo group into the 4-position of the naphthol nucleus and the additional introduction of the sulfo group into said fi-naphthylazo group. The sulfo group of the coupler in this invention may be free acid or its salt Without any difference in its function. v

The following examples illustrate couplers which may be used according to our invention. However, couplers of this invention will not be restricted only thereto.

TABLE OF COUPLER FORMULAE C ONH SO H | N II N l SOsH (|)H O llB ifl C ONH 1 SOaH N H N 0 uHa;

C ONI'I J SOaH l i N SOaH (III) O C rsHu COONH SOSH Z 2-? Z I I 0 rs a1 CONH SOaH

I O?ra :1

SOa s 0 (I) nHn coma-Q I SOaHa COOI-I (VII) (VIII) (|)H O Cir-JIM C ONH I N II N I I SOaH It will be shown that couplers of this invention demonstrate excellent properties, using the following control couplers, i.e., A containing a phenylazo group, B containing an a-naphthylazo group and C containing a B-naphthylazo group.

Compound (I) and comparative coupler A, B and C each is weighed in a given amount, dissolved in a small amount of l N caustic soda solution, diluted with a phosphate butter solution of pH 7.0 to prepare a solution of 4X 10* mols at a pH-value of 7.0 respectively and their spectral absorption curves are measured.

The curve in which the maximum absorption density attains 1.0 is shown in FIG. 1. The spectral absorption curve of compound (I) in a film obtained in Example 1 (I)/F, the spectral absorption curve of compound (I) in said aqueous solution (I)/W and the spectral absorption curve of compound (A) in a film (A)F are shown graphically in FIG. 2, in which the maximum absorption density makes to 1.0.

From FIG. 1, it is seen that B and C each have a very much longer spectral absorption maximum than that of compound (A) and that (B) and (C), more especially (B), have high blue and red absorption. From the comparison of FIG. 1 with FIG. 2, it is seen that compound (I) in aqueous solution shows a lower blue and red absorption than that of (B) or (C) and that the spectral absorption characteristics of compound (I) in a film has a longer spectral absorption maximum, by about 20 m compared with that in aqueous solution. From the spectral absorption characteristics of compound (I) in a film, it will be understood that said compound complies with the purposes of this invention more fully than compound (A).

The couplers of this invention were prepared as follows: Compound of formula I.l-hydroxy-4-(S-sulfo-fl-naphthylazo)-2-(2-octadecyloxy-5-sulfo)naphthanilide 7 g. of 2-naphthylamine-8-sulfonic acid and 1.5 g. of

caustic soda were dissolved in 50 ml. of water. 3 g. of

sodium nitrite and a small amount of crushed ice were added thereto and cooled to 0 C. 10 ml. of 36% hydrochloric acid was added to the solution with stirring.

18 g. of triethylamine salt of l-hydroxy-Z-(Z-octadecyloxy-S-sulfo) naphthanilide and 12 g. of caustic soda were dissolved in 400 ml. of water and cooled with ice to 5 C. The solution of diazonium salt prepared previously was added drop wise to the solution with stirring. After stirring for one hour, 300 ml. of 36% hydrochloric acid and then 500 ml. of acetonitrile are added. The resulting precipitates were filtered, washed with 300 ml. of acetonitrile and dissolved in 300 ml. of dimethylformamide with heating. 300 ml. of acetonitrile was added to the solution and the resulting precipitates were filtered to yield the end product.

The yield was 15 g. (71 and the melting point was above 280 C.

Compound of formula IV.l-hydroxy-4-(4,8-disulfo-fithylazo -2- 2-dodecloxy-5-sulfo) naphthanilide 9 g. of 2-naphthylamine-4,8disulfonic acid was used instead of 2-naphthylamine-S-sulfonic acid in (I) and otherwise the same procedure as in (I) was performed to yield the end product.

The yield was 14 g. (66%) and the melting point was above 280 C. Compound of formula II.-1-hydroxy-4-(6-sulfo-fi-naphthylazo)-2-(2-dodecloxy-5-sulfo naphthanilide 2-naphthylamine6-sulfonic acid instead of Z-naphthylamine-8-sulfonic acid and 14 g. of sodium salt of lhydroxy-2-(2-dodecycloxy-5-sulfo) naphthanilide instead of triethylamine salt of 1-hydroxy-2-(2-octadecyloxy-5- sulfo) naphthanilide were used in (I) and otherwise the same procedure as in (I) is performed to yield the end product.

The yield was 12 g. (611%) and the melting point was above 280 C.

Melting points and nitrogen analyses values of typical examples of the couplers of this invention are shown as in the table below.

TABLE Nitrogen 3M) M.P. Cale found 8-SO3H Above 280 C 4. 97 4. 73

6-SO H d 5. 16

l-SO H 4. 80

4, s-sonr 4. 24

3, 6-SO H 4. 67

VII 01811 1 -SO3H 4. 81 VIII C18H37 6, 8-SO H 4. 32

The examples of this invention will be described as follows and the object of this invention and other objects will be illustrated by the description of examples.

Example 1 N,N-diethyl-p-aminoanilinesulfate, g. 2.0 Anhydrous sodium sulfite, g 20.0 Sodium carbonate (monohydrate) 50.0 Hydroxylamine hydrochloride 1.5 Potassium bromide 1.0

Water, up to 1,000 ml. H="10.8i0.1).

It was then bleached and fixed with the bleaching and fixing solution of the following composition, and both undeveloped silver halide and reduced silver formed were removed to yield a cyan negative image and a magenta positive image consisting of the residual unreacted colored coupler.

Bleaching solution:

Potassium ferricynanide, g 100 Potassium bromide 20 Water, up to 1,000 ml. (pH- 6.9 0.3).

Fixing solution: Sodium thiosulfate (hypo). g. ...r 200 Anhydrous sodium sulfite 20 8. Acetic acid (28% ml. 45 Boric acid(crystaline) 7.5 Potassium alum 20 Water, up to 1,000 ml. (pH=4.5 012).

The maximum spectral absorption wave length of positive image obtained was 530 mp showing a desirable magenta color. The color of the positive image obtained was almost unchanged even by passing it through a stabilizing bath varying the pH-value from 4 to 11 (see Fig. 2).

Example 2 An equivalent amount of 1.5x 10 mols of N-n-octadecyl-l-hydroxy-4-sulfo 2 naphthamide sodium salt in aqueous 5% caustic soda solution was added to g. of sensitive emulsion containing panchromatic sensitizer. An equivalent amount of 1.0x 10 mols of said salt and an equivalent amount of 0.5x 10* mols of compound (I), (IV) and (V) in aqueous 5% caustic soda solution were respectively added to said emulsion in the same manner as in Example 1 to obtain red sensitive materials.

They were exposed through an optical wedge to red light, developed and fixed in the same manner as in Example 1 to obtain both a cyan negative image and positive magenta image, of which densities were measured to obtain the following result:

The characteristic curve in which the undesirable green absorption is masked is shown in FIG. 3. In FIG. 3, the solid line shows the use of compound (I) in admixture with N-n-octadecyl-1-hydroxy-4-sulfo-Z-naphthamide sodium salt and the dotted line shows the use of N-n-octadecyl-1-hydroxy-4-sulfo-Z-naphthamide sodium salt alone. 1 is the cyan density on using a red filter and 2 that on using a green filter. From the fact mentioned above, it will be understood that the coupler of this invention has no desensitization and little occurence of fog so that it has a suitable spectral absorption characteristic.

What is claimed is:

1. A color photographic silver halide emulsion containing a color coupler having the formula:

C ONH SOaM wherein R represents an alkyl group having more than 10 carbon atoms; M represents a member selected from the group consisting of hydrogen, an alkali metal, an ammonium group, and H.NH ,(R") where p is an integer selected from the group 0 to 3, q is an integer selected from the group 0 to 3 inclusive, p-|-q=3, and R" is a lower alkyl group; and n is an integer selected from the group 1 to 2 inclusive.

9 10 2. The color photographic emulsion of claim 1, wherein 6. The color photographic emulsion of claim 1, wheresaid color coupler is: in said color coupler is OH OCmHat H OCnHn l I CONH OONH l I SOBH 50111 if E N 7. The color photographic emulsion of claim 1, wherein said color coupler is 3. The color photographic emulsion of claim 1, where- OH 0012K in said color coupler 1s CONH 0H (|)C12HI$ SOaH CONH 'll;

8. The color photographic emulsion of claim 1, wherein said color coupler is SOSH 11 OCnHmv COHN 4. The color photographic emulsion of claim 1, where- 40 SOSH in said color coupler is I N II i N 00 H I l! 1? 0 ONE 803B SOHz '1 9. The color photographic emulsion of claim 1, wherein said color coupler is H 038 (H1 0 0 "H 1 ooNH- I 5. The color photographic emulsion of claim 1, wheref in said color coupler is 1i 03 OCIIHH CON H SOaH 803E References Cited I! UNITED STATES PATENTS t 2,688,539 9/ 1954 Heimbach et al 96-100 2,979,405 4/1961 DeCat et a1 96-100 $0111 I. TRAVIS BROWN, Primary Examiner HOIS- US. Cl. X.R. 

